This also applies to cable, chain, and webbing.
Gear that is anchored includes anchors, rocks, trees, tripods, trucks, etc.
A "bight" is a simple loop in a rope that does not cross itself.
A "bend" is a knot that joins two ropes together. Bends can only be attached to the end of a rope.
A "hitch" is a type of knot that must be tied around another object.
"Descending devices" (e.g., ATCs, Brake Bar Racks, Figure 8s, Rescue 8s, etc) create friction as their primary purpose. The friction in descending devices is always considered when calculating forces.
The "Safety Factor" is the ratio between the gear's breaking strength and the maximum load applied to the gear (e.g., 5:1).
If you attempt to calculate forces when there is more than one item that can pull or release rope, a message will be displayed and the items that can pull or release rope will be selected. This message is displayed because vRigger can't accurately calculate forces when there is more than one item that can pull or release rope.
In this case, all of the pullers are treated as anchors and will hold the rope stationary. vRigger won't be able to accurately calculate the effects of friction because it won't know if the load is being raised or lowered, and it won't be able to display the mechanical advantage on the status bar.
However, you can select all but one of the items that can pull and release rope and set the Direction field in the properties pane to Holding. Doing so will instruct vRigger to ignore those items when determining the number of items that can pull or release rope. In the following system, only the rightmost man is pulling—the others are holding the rope.
When the other pullers are set to Holding, vRigger will calculate the forces correctly. However, as shown below, all of the force will be assigned to the one item that is pulling.
To correct this visually, you can select all of the pullers, change the Show Forces option in the properties pane to Never, and then use the Text tool to display forces next to the pullers (e.g., "20 lb" in this case). You can also select the rope and change its Show Forces option to Never. These two steps will allow vRigger to automatically label the forces on the other items in the system.
